The hardcover version of a book weighs 7 ounces while its paperback version weighs 5 ounces. Forty-five copies of the book weigh a total of 249 ounces. Weight of Books Number of Books Weight per book (ounces) Total Weight (ounces) Hard Cover h 7 7 h Paperback 45 minus h 5 x Total 45 249 Which value could replace x in the table?